Photographic-printing machine



May 8, 1928.

D. M KENZlE PHOTOGRAPHIC PRINTINGMACHINE Filed April 8. 1924 Patented May 8, 1928.

UNITED STATES PATENT OFFICE.

i DOITALD MAGKENZIE, OF EAST OBANGE, NEW J'ERSEY, ASSIGNOR TO WESTERN ELEG- TRIC COMPANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

. Application filed April 8,

' This invention relates to means for and the method of reproducing sound and motion pictures in synchronism. More specifically, this invention provides means for simplifying the print-ing of picture and sound records from a negative film onto a single positive film at the same time and by the same printing machine.

Due to variations in lighting conditions and in the character of the objects being photographed motion picture negatives may vary greatly in average contrast throughout, the length of a single roll ot film. It is customary to correct for this by Varying the 1 intensity of the light used for making positive records from the negatives. Sound records on negative films on the other hand may be produced under more easily controllable conditions, so that usually no such correction is required or desirable, or, if required, the correction will he different from that of the corresponding portion of the picture record.

In accordance with this invention sepa- 26 rate lighting means are used for the picture record and the sound record respectively. With this arrangement the amount of exposure of the positive motion picture record can be varied without correspondingly varying the exposure of the sound record, and if desired the exposure of the sound record can `be independently varied.

A feature of the invention is the provision of an auxiliary lighting means which can be readily attached to existing printing machines.

` This invention will be best understood by the following description and the claim appended thereto, reference being had to the &0 accompanying drawings in which Fig. 1 is a sectional view of a portion of the printing machine taken approximately on line 1-1 of Fig. 2.

Fig. 2 is a partial front view of Fi g. 1.

Similar reference characters refer to similar parts throughout the several views.

The numeral 10 designates a portion of the casing on which the Operating mecha nism is mounted. This casing 10 is provided 'with a chamber 11 in which an incandescent lamp 12 is mounted and adapted to furnish the light for printing thepictures on the positive film 13 from the negative film 14. These films are operatively mounted on a 1924. Serial No. 704304.

duplex sprocket wheel 15 (shown in Fig. 2) which is preferably rotated at a uniform rate of speed by any suitable actuating mechanism (not shown).- Negative film 13 and positive film 14 thread through a path defined by a plurality of rollers 17 and 18 and are held against the guide 19 and the adjustable Shutter 20 by means of a spring pressed member 21 which is provided with a finger hold 22. This member 21 is pivoted on the shaft 23 which is secured to the frame of the machine. The apparatus just described is typical of motion picture print incr machines now in use, except that the le t hand end of the opening between member 19 and shutter 20 has been closed to prevent light from lamp 12 from striking the narrow band of the film containing the sound record.

On the upper part of casing 10 there is mounted a support 24: on which an L shaped casing 28 is Secured. In the top portion of this casing there is mounted an incandescent lamp 25 from which the light rays are directed against a plane mirror 26 provided to divert the light rays at right angles from their source into a rectangular shaped aperture 27 disposed in juxtaposition withthe sound rcproducing record of the negative film 14 as shown in Fig. 2. The operation of the machine is as follows: The negative and the positive film are mounted on a plurality of rollers and are actuated by means of an ordinary duplex sprocket wheel which may be rotated through the movement of.

any suitable Operating mechanism shown).

The portion of the negative film 14, carrying the sound record together with the portion of the positive film on which the sound record .is to be printed pass in front of the aperture 27 which is made in a portion of the lighting chambcr 28 shown in Fig. 1. The beam of light generated by the incandescent lamp 25 is projected into this aperture onto the films by means of the plane mirror 26 which is disposed to deflect the light rays at right angles with respect to their generating source. It is understood that the intensity of light of the incandescent lamps 12 and 25 may be adjusted if desired by controlling the flow of current through the lamps.

The picture record is disposed by the side (not of the sound' record and ptsses in front of its respective' aperture in the light-ing chamber 11-; This lighting hmber isprovided With anadjustable Shutter adapted, for con'- i &trolling thetme exposure of the pictures.

By theuse 'of .thisinvention it is ohvous V that the best results in the picture and sound ,records may he ohtained in the development of the film'. v t e That is claimed isi' and& sound record thereon, means for iconytinuously progressing said film, means for' 15 progressng a senstized positive film simul taneouslywith said negative film and means In a r photographic printing machine, a- 4 negative film having both a pcture record for printing the sound record independently of the picture record. comprisng, an -L- .aperturedisposed to register With the sound portion ofthenegative hn and e defiector f for deflectingt-he light rays onto the apertured portion ot said L-shaped casing:

In wtness whereot,I-.hereunto subscribe ny name this 27th day of' March, A. D.

DONA-LD JSACKENZIE. 

